cancelling

Self-cancel: go to https://account.adobe.com/plans, and click “Manage Plan”.  If you have problems with that, contact Adobe customer support: Adobe customer care can be contacted by beginning a secure chat session at https://helpx.adobe.com/contact.html?rghtup=autoOpen. Pop-up blockers need to be disabled, you need to accept cookies! If the chat window fails to open, or is non-responsive, use a different device and/or browser to start the interaction.

For support via Twitter:
https://twitter.com/AdobeCare

(see also here: https://community.adobe.com/t5/creative-cloud-services/how-to-contact-adobe-support/td-p/11875703 or here
https://community.adobe.com/t5/account-payment-plan/how-to-contact-adobe-support/td-p/11843852)

Important: Adobe does NOT contact you unsolicited by e-mail or direct message. If you get contacted by direct message from a person, claiming to be an Adobe employee, look at that profile and look, if they bear the “Adobe Employee” marking under their name. Adobe support does not use Skype to give you support.
If in doubt, ask the forum.

make sure you're aware of the cancellation terms by selecting your plan type (at the top of the page here), https://helpx.adobe.com/manage-account/using/creative-cloud-subscription-terms.html

for info on how to cancel your subscription, this page describes the few steps involved, https://helpx.adobe.com/manage-account/using/cancel-subscription.html

if you want to cancel but are unable to follow the steps described in the "how to cancel page", contact adobe support.

there are 2 ways to contact adobe; chat and twitter (now x):

chat:
use a browser that allows popups and cookies, and click here, https://helpx.adobe.com/contact.html?rghtup=autoOpen
in the chat field (lower right), type AGENT
be patient, it can take quite a while to reach a human.

twitter/x:
tweet @AdobeCare

p.s. if you're contacted by anyone (via email or private message), it's much more likely to be a scammer than an adobe representative.

You should be able to cancel your subscription from your account.

Note though that , depending on your plan, termination charges may apply

https://www.adobe.com/uk/legal/subscription-terms.html

Dave